Symptomatic atlantoaxial dislocation in Down's syndrome.

Four patients with Down's syndrome suffered compression of the spinal cord secondary to atlantoaxial dislocation. All four developed inability to walk and quadriparesis, with signs of cervical myelopathy. It is important to recognize this potentially fatal complication of the syndrome. Immediate immobilization of the neck, followed by cervical roentgenograms, should be done in any patient with Down's syndrome who presents with neck pain, torticollis, urinary incontinence, or loss of ambulation. Surgical repair with fusion of the first and second cervical vertebrae can be carried out later.